<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        @import url("test.css");
   </style>
    <link rel="stylesheet" href="./a.css">
    <!-- <style>
        div {
            color: red;
        }
    </style> -->
</head>

<body>
    <div>dada</div>
</body>

</html>